Index Features and advantages... 3 General characteristics... 5 Nomenclature... 9 Technical Specifications Sound levels...

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2 Index Features and advantages... 3 Features and advantages... 3 Seasonal quietness... 3 Infinitely capacity control... 3 Code requirements Safety and observant of laws/directives... 3 Certifications... 4 Versions... 4 Sound configuration... 4 General characteristics... 5 Cabinet and structure... 5 Screw compressors... 5 Ecological HFC 134a refrigerant... 5 Evaporator... 5 Condenser... 5 Electronic expansion valve... 5 Refrigerant Circuit... 5 Electrical control panel... 6 Standard accessories (supplied on basic unit)... 7 Nomenclature... 9 Technical Specifications EWWD~J-SS Sound levels Sound pressure level correction for different distances Operating limits How to use the Correction factors proposed in the previous tables Water charge, flow and quality Water content in cooling circuits Standard ratings EWWD120~250J-SS EWWD280~400J-SS EWWD450~560J-SS Evaporator and condenser pressure drops EWWD~J-SS Dimensions EWWD~J-SS / 1 circuit EWWD~J-SS / 2 circuits Installation notes Warning Warning Handling Location Minimum space requirements Technical specification for water cooled screw chillers General Refrigerant Performance Unit description Noise level and vibration Dimension Chiller components page 2/36

3 Features and advantages Features and advantages The EWWD~J- water cooled chillers, featuring 1 or 2 single screw compressors, are manufactured to satisfy the requirements of the consultants and the end user. Units are designed to minimise energy costs while maximising the refrigeration capacities. Daikin s chiller design experience, combined with outstanding features makes the EWWD~J- chiller unmatched in the industry. Seasonal quietness The compressor design with a single screw and twin rotors allows a constant gas flow. This compression process completely eliminates gas pulsations. The oil injection also results in significant mechanical noise reduction. The twin gas compressor discharge chambers are designed to act as attenuators, based on the harmonic wave principle with destructive interference, thus always resulting equal to zero. The extremely low noise compressor performance affords the use of EWWD~J- chiller for all applications. The reduced number of vibrations produced from the EWWD~J- chiller offers a surprisingly quiet operation eliminating the noise transmission through the structure and the chilled water piping system. Infinitely capacity control Cooling capacity control is infinitely variable by means of a screw compressor controlled by microprocessor system. Each unit has infinitely variable capacity control from 100% down to 25% (one compressor unit) and down to 12,5% (two compressors units). This modulation allows the compressor capacity to exactly match the building cooling load without any leaving evaporator water temperature fluctuation. This chilled water temperature fluctuation is avoided only with a stepless control. Building Load Compressor Load EWLT fluctuation with stepless capacity control With a compressor load step control in fact, the compressor capacity, at partial loads, will be too high or too low compared to the building cooling load. The result is an increase in chiller energy costs, particularly at the part-load conditions at which the chiller operates most of the time. Building Load Compressor Load time ELWT fluctuation with steps capacity control (4 steps) Units with stepless regulation offer benefits that the units with step regulation are unable to match. The ability to follow the system energy demand at any time and the possibility to provide steady outlet water temperature without deviations from the set-point, are the two points that allow you to understand how the optimum operating conditions of a system can be met only through the use of a unit with step-less regulation. Code requirements Safety and observant of laws/directives All water cooled units are designed and manufactured in accordance with applicable selections of the following: Construction of pressure vessel 97/23/EC (PED) Machinery Directive 2006/42/EC Low Voltage 2006/95/EC Electromagnetic Compatibility 2004/108/EC Electrical & Safety codes EN / EN Manufacturing Quality Stds UNI EN ISO 9001:2004 page 3/36

4 Certifications All units manufactured are CE marked, complying with European directives in force, concerning manufacturing and safety. On request units can be produced complying with laws in force in non European countries (ASME, GOST, etc.), and with other applications, such as naval (RINA, etc.). Versions EWWD~J- is available in standard efficiency version: S: Standard Efficiency 16 sizes, covering a cooling capacity range from 121 up to 571 kw, EER up to 4.41 and ESEER up to The EER (Energy Efficiency Ratio) is the ratio of the Cooling Capacity to the Power Input of the unit. The Power Input includes: the power input for operation of the compressor, the power input of all control and safety devices. The ESEER (European Seasonal Energy Efficiency Ratio) is a weighed formula enabling to take into account the variation of EER with the load rate and the variation of water inlet condenser temperature. ESEER = A x EER 100% + B x EER 75% + C x EER 50% + D x EER 25% A B C D Coefficient 0.03 (3%) 0.33 (33%) 0.41 (41%) 0.23 (23%) Condenser water inlet temperature ( C) Sound configuration EWWD~J- is available in standard sound level configuration: S: Standard Noise page 4/36

5 General characteristics Cabinet and structure The cabinet is made of galvanized steel sheet and painted to provide a high resistance to corrosion. Colour Ivory White (Munsell code 5Y7.5/1) (±RAL7044).The base frame has eye-hook for lifting the unit with ropes for an easy installation. The weight is uniformly distributed along the profiles of the base and this facilitates the arrangement of the unit. Screw compressors The compressor is semi-hermetic, single-screw type with gate-rotors made of carbon impregnated engineered composite material. The compressor has one slide managed by the unit microprocessor for infinitely modulating the capacity between 100% to 25%. An integrated high efficiency oil separator maximizes the oil separation and standard start is Wye-delta (Y-Δ) type. Ecological HFC 134a refrigerant The compressors have been designed to operate with R-134a, ecological refrigerant with zero ODP (Ozone Depletion Potential) and very low GWP (Global Warming Potential) that means low TEWI (Total Equivalent Warming Impact). Evaporator The units are equipped with direct expansion plate to plate type evaporator, one per circuit. This heat exchanger is made of stainless steel brazed plates and is covered with a 10mm closed cell insulation material. The evaporator is manufactured in accordance to PED approval. The evaporator water outlet connections are provided with Victaulic Kit (as standard). Condenser The units are equipped with Direct Expansion shell & tube condenser, with copper tubes rolled into steel tube sheets. The unit has independent condensers, one per circuit. The condenser is manufactured in accordance to PED approval. Condensers are provided with liquid shut-off valve and spring loaded relief valve. The condenser water outlet connections are provided with Victaulic Kit (as standard). Electronic expansion valve The unit is equipped with the most advanced electronic expansion valves to achieve precise control of refrigerant mass flow. As today s system requires improved energy efficiency, tighter temperature control, wider range of operating conditions and incorporate features like remote monitoring and diagnostics, the application of electronic expansion valves becomes mandatory. Electronic expansion valve proposes features that make it unique: short opening and closing time, high resolution, positive shut-off function to eliminate use of additional solenoid valve, highly linear flow capacity, continuous modulation of mass flow without stress in the refrigerant circuit and corrosion resistance stainless steel body. Electronic expansion valve strength point is the capacity to work with lower ΔP between high and low pressure side, than a thermostatic expansion valve. The electronic expansion valve allows the system to work with low condenser pressure (winter time) without any refrigerant flow problems and with a perfect chilled water leaving temperature control. Refrigerant Circuit Each unit has independent refrigerant circuits and each one includes: Single screw compressor with integrated oil separator Brazed plate evaporator Shell & tube condenser Oil pressure transducer High pressure switches High pressure transducer Low pressure transducer Moisture liquid indicator Replaceable core filter-drier Electronic expansion valve page 5/36

6 Electrical control panel Power and control are located in the main panel that is manufactured to ensure protection against all weather conditions. The electrical panel is IP54 and (when opening the doors) internally protected with Plexiglas panel against possible accidental contact with electrical components (IP20). The main panel is fitted with a main switch interlocked door. Power Section The power section includes compressors fuses and control circuit transformer. MicroTech III controller MicroTech III controller is installed as standard; it can be used to modify unit set-points and check control parameters. A built-in display shows chiller operating status plus temperatures and pressures of water, refrigerant, programmable values, set-points. A sophisticated software with predictive logic, selects the most energy efficient combination of compressors and electronic expansion valve to keep stable operating conditions to maximise chiller energy efficiency and reliability. MicroTech III is able to protect critical components based on external signs from its system (such as motor temperatures, refrigerant gas and oil pressures, correct phase sequence, pressure switches and evaporator). The input coming from the high pressure switch cuts all digital output from the controller in less than 50ms, this is an additional security for the equipment. Fast program cycle (200ms) for a precise monitoring of the system. Floating point calculations supported for increased accuracy in P/T conversions. Control section - main features Management of the compressor stepless capacity. Chiller enabled to work in partial failure condition. Full routine operation at condition of: - high ambient temperature value - high thermal load - high evaporator entering water temperature (start-up) Display of evaporator entering/leaving water temperatures. Display of condensing-evaporating temperatures and pressures, suction and discharge superheat for each circuit. Leaving water evaporator temperature regulation. Temperature tolerance = 0,1 C. Compressor and evaporator pumps hour counters. Display of Status Safety Devices. Number of starts and compressor working hours. Optimized management of compressor load. Re-start in case of power failure (automatic / manual). Soft Load (optimized management of the compressor load during the start-up). Start at high evaporator water temperature. Return Reset (Set Point Reset based on return water temperature). Set point Reset (optional). Application and system upgrade with commercial SD cards. Ethernet port for remote or local servicing using standard web browsers. Two different sets of default parameters could be stored for easy restore. Safety device / logic for each refrigerant circuit High pressure (pressure switch). High pressure (transducer). Low pressure (transducer). High compressor discharge temperature. High motor winding temperature. Phase Monitor. Low pressure ratio. High oil pressure drop Low oil pressure. page 6/36

7 No pressure change at start. System security Phase monitor. Low Ambient temperature lock-out. Freeze protection. Regulation type Proportional + integral + derivative regulation on the evaporator leaving water output probe. MicroTech III MicroTech III built-in terminal has the following features. 164x44 dots liquid crystal display with white back lighting. Supports Unicode fonts for multi-lingual. Key-pad consisting of 3 keys. Push n Roll control for an increased usability. Memory to protect the data. General faults alarm relays. Password access to modify the setting. Application security to prevent application tampering or hardware usability with third party applications. Service report displaying all running hours and general conditions. Alarm history memory to allow an easy fault analysis. Supervising systems (on request) MicroTech III remote control MicroTech III is able to communicate to BMS (Building Management System) based on the most common protocols as: ModbusRTU LonWorks, now also based on the international 8040 Standard Chiller Profile and LonMark Technology BacNet BTP certifief over IP and MS/TP (class 4) (Native) Chiller Sequencing MicroTech III controller allows an easy plug-in sequencing technology based on digital or serial panel Digital Sequencing Panel This panel is basically a step inserter that switches ON/OFF up to 11 units (chillers or heat pumps operating in the same cooling/heating mode) depending on the selected set point; the units are connected with the panel through standard cables and no serial card is requested. Serial Sequencing Panel Basically this panel sequences a chiller plant by switching on/off the units (up to 7 chillers) taking into account their running hours and the requested plant load, in order to optimise the number of working units for each condition; serial cards and shielded cables are requested to connect the panel with the units and, if installed, a BMS. Standard accessories (supplied on basic unit) Evaporator Victaulic Kit - Hydraulic joint with gasket for an easy and quick water connection. 20mm Evaporator Insulation Condenser Victaulic kit Condenser Water side design pressure 16 bar Condenser 2 passes (Δt 4-8 C) Suction line shut off valve - Suction shut-off valve installed on the suction of the compressor to facilitate maintenance operation. Discharge line shut-off valves - Discharge shut-off valve installed on the discharge of the compressor to facilitate maintenance operations. Electronic Expansion Valve page 7/36

8 High Pressure Side Manometers Y-D starter - Star Delta starter is the standard type Double set-point - Dual leaving water temperature set-points. Phase monitor - The phase monitor controls that phases sequence is correct and controls phase loss. Evaporator flow switch for the water piping Hour Run meter - Digital compressors hour run meter General fault contactor - Contactor for alarm warning. Main switch interlock Emergency stop Options (on request) Heat pump version Brine version Allows the unit to operate down to -8 C leaving liquid temperature (antifreeze required). Compressor thermal overload relays - Safety devices against compressor motor overloading in addition to the normal protection envisaged by the electrical windings. Evaporator Water side design pressure 16 bar 20mm Condenser insulation Condenser double flanges kit Water pressure differential switch on evaporator Sound Proof System - Compressor sound enclosure. Rubber type antivibration mounts Supplied separately, these are positioned under the base of the unit during installation. Ideal to reduce the vibrations when the unit is floor mounted Fork lift kit Low pressure side manometers Dual Pressure Relief Valve on evaporator Under/Over Voltage This device control the voltage value of power supply and stop the chiller if the value exceeds the allowed operating limits. Energy Meter This device allows to measure the energy absorbed by the chiller during its life. It is installed inside the control box mounted on a DIN rail and show on a digital display: Line-to-Line Voltage, Phase and Average Current, Active and Reactive Power, Active Energy, Frequency. Condenser power factor correction - Installed on the electrical control panel to ensure it conforms to the plant rules. (Daikin advices maximum 0,9). Current limit display Witness test Every unit is always tested at the test bench prior to the shipment. On request, a second test can be carried out, at customer s presence, in accordance with the procedures indicated on the test form. (Not available for units with glycol mixtures). Acoustic test On request, a test can be carried out, at customer s presence (please contact the factory) (This test is not available for units with glycol mixtures). Set-point reset, demand limit and alarm from external device The leaving water temperature set-point can be overwritten with the following options: 4-20mA from external source (by user); outside ambient temperature; evaporator water temperature Δt. Moreover the device allow the user to limit the load of the unit by 4-20mA signal or by network system and the microprocessor is able to receive an alarm signal from an external device (pump etc - user can decide if this alarm signal will stop or not the unit). Automatic circuit breakers page 8/36

9 Nomenclature E W W D J - S S Machine type EWA = Air-cooled chiller, cooling only EWY = Air-cooled chiller, heat pump EWL = Remote condenser chiller ERA = Air cooled condensing unit EWW = Water-cooled chiller, cooling only EWC = Air-cooled chiller, cooling only with centrifugal fan EWT = Air-cooled chiller, cooling only with heat recovery Refrigerant D = R-134a P = R-407c Q = R-410a Capacity class in kw (Cooling) Always 3-digit code Idem as previous Model series Letter A, B, : major modification Inverter - = Non-inverter Z = Inverter Efficiency level S = Standard efficiency X = High efficiency (N.A for this range) P = Premium efficiency (N.A for this range) Sound level S = Standard noise L = Low noise (N.A for this range) R = Reduced noise (N.A for this range) X = Extra low noise (N.A for this range) C = Cabinet (N.A for this range) Warranty 0 = 1 year of warranty B = 2 years of warranty C = 3 years of warranty =... years of warranty Sequential number 000 = Base model 001 = First order for this model (1 or more units) 002 = Second order for this model (1 or more units) =... order for this model B01 = First order for this model + 1year warranty B02 = Second order for this model (1 or more units) =... order for this model page 9/36

10 Technical Specifications EWWD~J-SS TECHNICAL SPECIFICATIONS EWWD~J-SS Capacity (1) Cooling kw Type Stepless Capacity control Minimum capacity % Unit power input (1) Cooling kw EER (1) ESEER Capacity (2) Heating kw Unit power input (2) Heating kw COP (2) Casing Colour Ivory White Material Galvanized and painted steel sheet Dimensions Weight Water heat exchanger Evaporator Water heat exchanger Condenser Unit Unit Operating Weight Type Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Type Number of condenser Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Height mm Width mm Length mm kg kg Brased plate, one per circuit l Cooling l/s Cooling kpa No. Closed cell Double Pass Shell&Tube One per circuit l Cooling l/s Cooling kpa Closed cell Semi-hermetic Type single screw compressor Compressor Oil charge l Quantity No Sound level Sound Power (3) Cooling db(a) Sound Pressure (3) Cooling db(a) Refrigerant type R134a Refrigerant circuit Refrigerant charge kg N. of circuits No Piping connections Evaporator water inlet/outlet mm Piping connections Condenser water inlet/outlet inc. 2 1/2 " 4" 4" 4" Safety devices High discharge pressure (pressure switch) High discharge pressure (pressure transducer) Low suction pressure (pressure transducer) Compressor motor protection High discharge temperature Low oil pressure Low pressure ratio High oil filter pressure drop Phase monitor Emergency stop button Water freeze protection controller Notes (1) Notes (2) Notes (3) Cooling capacity, unit power input in cooling and EER are based on the following conditions: evaporator 12/7 C; condenser 30/35 C, unit at full load operation. Heating capacity, unit power input in cooling and COP are based on the following conditions: evaporator 12/7 C; condenser 40/45 C, unit at full load operation. The values are according to ISO 3744 and are referred to: evaporator 12/7 C, condenser 30/35 C, full load operation. page 10/36

11 TECHNICAL SPECIFICATIONS EWWD~J-SS Capacity (1) Cooling kw Capacity control Type Stepless Minimum capacity % Unit power input (1) Cooling kw EER (1) ESEER Capacity (2) Heating kw Unit power input (2) Heating kw COP (2) Casing Colour Ivory White Material Galvanized and painted steel sheet Dimensions Weight Water heat exchanger Evaporator Water heat exchanger Condenser Unit Unit Operating Weight Type Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Type Number of condenser Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Height mm Width mm Length mm kg kg Brased plate, one per circuit l Cooling l/s Cooling kpa Closed cell No. Double Pass Shell&Tube One per circuit l Cooling l/s Cooling kpa Closed cell Semi-hermetic Type single screw compressor Compressor Oil charge l Quantity No Sound level Sound Power (3) Cooling db(a) Sound Pressure (3) Cooling db(a) Refrigerant type R134a Refrigerant circuit Refrigerant charge kg N. of circuits No Piping connections Evaporator water inlet/outlet mm Piping connections Condenser water inlet/outlet inc. 4" 4" 4" 4" Safety devices High discharge pressure (pressure switch) High discharge pressure (pressure transducer) Low suction pressure (pressure transducer) Compressor motor protection High discharge temperature Low oil pressure Low pressure ratio High oil filter pressure drop Phase monitor Emergency stop button Water freeze protection controller Notes (1) Notes (2) Notes (3) Cooling capacity, unit power input in cooling and EER are based on the following conditions: evaporator 12/7 C; condenser 30/35 C, unit at full load operation. Heating capacity, unit power input in cooling and COP are based on the following conditions: evaporator 12/7 C; condenser 40/45 C, unit at full load operation. The values are according to ISO 3744 and are referred to: evaporator 12/7 C, condenser 30/35 C, full load operation. page 11/36

12 TECHNICAL SPECIFICATIONS EWWD~J-SS Capacity (1) Cooling kw Capacity control Type Stepless Minimum capacity % Unit power input (1) Cooling kw EER (1) ESEER Capacity (2) Heating kw Unit power input (2) Heating kw COP (2) Casing Colour Ivory White Material Galvanized and painted steel sheet Dimensions Weight Water heat exchanger Evaporator Water heat exchanger Condenser Unit Unit Operating Weight Type Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Type Number of condenser Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Height mm Width mm Length mm kg kg Brased plate, one per circuit l Cooling l/s Cooling kpa Closed cell No. Double Pass Shell&Tube One per circuit l Cooling l/s Cooling kpa Closed cell Semi-hermetic single screw compressor l No Cooling db(a) Cooling db(a) R134a kg No Type Compressor Oil charge Quantity Sound level Sound Power (3) Sound Pressure (3) Refrigerant type Refrigerant circuit Refrigerant charge N. of circuits Piping connections Evaporator water inlet/outlet mm Piping connections Condenser water inlet/outlet inc. 4" 4" 4" 4" Safety devices High discharge pressure (pressure switch) High discharge pressure (pressure transducer) Low suction pressure (pressure transducer) Compressor motor protection High discharge temperature Low oil pressure Low pressure ratio High oil filter pressure drop Phase monitor Emergency stop button Water freeze protection controller Notes (1) Notes (2) Notes (3) Cooling capacity, unit power input in cooling and EER are based on the following conditions: evaporator 12/7 C; condenser 30/35 C, unit at full load operation. Heating capacity, unit power input in cooling and COP are based on the following conditions: evaporator 12/7 C; condenser 40/45 C, unit at full load operation. The values are according to ISO 3744 and are referred to: evaporator 12/7 C, condenser 30/35 C, full load operation. page 12/36

13 TECHNICAL SPECIFICATIONS EWWD~J-SS Capacity (1) Cooling kw Capacity control Type Stepless Minimum capacity % Unit power input (1) Cooling kw EER (1) ESEER Capacity (2) Heating kw Unit power input (2) Heating kw COP (2) Casing Colour Ivory White Material Galvanized and painted steel sheet Height mm Dimensions Unit Width mm Length mm Weight Unit kg Operating Weight kg Type Brased plate, one per circuit Water volume l Water heat exchanger Nominal water flow rate Cooling l/s Evaporator Nominal Water pressure drop Cooling kpa Insulation material Closed cell Type Number of condenser No. Double Pass Shell&Tube One per circuit Water heat exchanger Condenser Compressor Sound level Refrigerant circuit Water volume Nominal water flow rate Nominal Water pressure drop Insulation material Type Oil charge Quantity Sound Power (3) Sound Pressure (3) Refrigerant type Refrigerant charge N. of circuits l Cooling l/s Cooling kpa Closed cell Semi-hermetic single screw compressor l No Cooling db(a) Cooling db(a) R134a kg No Piping connections Evaporator water inlet/outlet mm Piping connections Condenser water inlet/outlet inc. 4" 4" 4" 4" Safety devices High discharge pressure (pressure switch) High discharge pressure (pressure transducer) Low suction pressure (pressure transducer) Compressor motor protection High discharge temperature Low oil pressure Low pressure ratio High oil filter pressure drop Phase monitor Emergency stop button Water freeze protection controller Notes (1) Notes (2) Notes (3) Cooling capacity, unit power input in cooling and EER are based on the following conditions: evaporator 12/7 C; condenser 30/35 C, unit at full load operation. Heating capacity, unit power input in cooling and COP are based on the following conditions: evaporator 12/7 C; condenser 40/45 C, unit at full load operation. The values are according to ISO 3744 and are referred to: evaporator 12/7 C, condenser 30/35 C, full load operation. page 13/36

14 ELECTRICAL SPECIFICATIONS EWWD~J-SS Phase Frequency Hz Power Supply Voltage V Voltage Tolerance Minimum % -10% -10% -10% -10% Maximum % +10% +10% +10% +10% Maximum starting current A Unit Nominal running current cooling A Maximum running current A Maximum current for wires sizing A Phase No Voltage V Compressor Voltage Tolerance Minimum % -10% -10% -10% -10% Maximum % +10% +10% +10% +10% Maximum running current A Starting method Wye Delta type (Y Δ) ELECTRICAL SPECIFICATIONS EWWD~J-SS Phase Frequency Hz Power Supply Voltage V Voltage Tolerance Minimum % -10% -10% -10% -10% Maximum % +10% +10% +10% +10% Maximum starting current A Unit Nominal running current cooling A Maximum running current A Maximum current for wires sizing A Phase No Voltage V Minimum % -10% -10% -10% -10% Voltage Tolerance Compressor Maximum % +10% +10% +10% +10% Maximum running current A Starting method Wye Delta type (Y Δ) Notes Allowed voltage tolerance ± 10%. Voltage unbalance between phases must be within ± 3% Maximum starting current: starting current of biggest compressor + current of compressors at 75% maximum load Nominal current in cooling mode refers to the following conditions: evaporator 12 C/7 C; condenser 30/35 C Maximum running current is based on max compressor absorbed current in its envelope Maximum unit current for wires sizing is based on minimum allowed voltage Maximum current for wires sizing: (compressors full load ampere) x 1,1 page 14/36

15 ELECTRICAL SPECIFICATIONS EWWD~J-SS Power Supply Unit Compressor Phase Frequency Voltage Voltage Tolerance Maximum starting current Nominal running current cooling Maximum running current Maximum current for wires sizing Phase Voltage Voltage Tolerance Hz V Minimum % -10% -10% -10% -10% Maximum % +10% +10% +10% +10% A A A A No V Minimum % -10% -10% -10% -10% Maximum % +10% +10% +10% +10% Maximum running current A Starting method Wye Delta type (Y Δ) ELECTRICAL SPECIFICATIONS EWWD~J-SS Power Supply Unit Compressor Phase Frequency Voltage Voltage Tolerance Maximum starting current Nominal running current cooling Maximum running current Maximum current for wires sizing Phase Voltage Voltage Tolerance Hz V Minimum % -10% -10% -10% -0.1 Maximum % +10% +10% +10% +10% A A A A No V Minimum % -10% -10% -10% -10% Maximum % +10% +10% +10% +10% Maximum running current A Starting method Wye Delta type (Y Δ) Notes Allowed voltage tolerance ± 10%. Voltage unbalance between phases must be within ± 3% Maximum starting current: starting current of biggest compressor + current of compressors at 75% maximum load Nominal current in cooling mode refers to the following conditions: evaporator 12 C/7 C; condenser 30/35 C Maximum running current is based on max compressor absorbed current in its envelope Maximum unit current for wires sizing is based on minimum allowed voltage Maximum current for wires sizing: (compressors full load ampere) x 1,1 page 15/36

16 Sound levels EWWD~J-SS Sound pressure level at 1 m from the unit in semispheric free field (rif. 2 x 10-5 Pa) Power Unit size 63 Hz 125 Hz 250 Hz 500 Hz 1000 Hz 2000 Hz 4000 Hz 8000 Hz db(a) db(a) (1) The values are according to ISO 3744 and are referred to: evaporator 12/7 C, condenser 30/35 C, full load operation. (2) The above sound pressure levels will decrease by 4dB(A) when a compressor sound enclosure (option) is installed. Sound pressure level correction for different distances Unit size Distance 1m 5m 10m 15m 20m 25m (1) The values are db(a) (pressure level). page 16/36

17 Operating limits Condenser Leaving Water Temp. ( C) Operation with Glycol ICE MODE Operation with Glycol (below 4 C Evap LWT) Evaporator Leaving Water Temp. ( C) Table 1 - Evaporator/Condenser minimum and maximum water Δt Max evaporator water Δt C 8 Min evaporator water Δt C 4 Min condenser water Δt C 4 Max condenser water Δt C 8 Table 2 - Evaporator fouling factors Fouling factors m 2 C / kw Cooling capacity correction factor Power input correction factor EER correction factor Table 3 - Condenser fouling factors Fouling factors Cooling capacity Power input EER m 2 C / kw correction factor correction factor correction factor Table Minimum glycol percentage for low water temperature Evaporator Leaving Water Temperature ( C) Ethylene glycol (%) Propylene glycol (%) Note: Minimum glycol percentage to be used with evaporator leaving water temperature below 4 C to prevent freezing of water circuit. page 17/36

18 Table Minimum glycol percentage for low air temperature Air Ambient Temperature ( C) (2) Ethylene glycol (%) (1) 10% 20% 30% 40% 50% Air Ambient Temperature ( C) (2) Propylene glycol (%) (1) 10% 20% 30% 40% 50% Note (1): Minimum glycol percentage to prevent freezing of water circuit at indicated air ambient temperature Note (2): Air ambient temperature do exceed the operating limits of the unit, as protection of water circuit may be needed in winter season at non-working conditions Table 5 - Correction factors for low evaporator leaving water temperature Evaporator Leaving Water Temperature ( C) Cooling Capacity Compressor Power Input Note: Correction factors have to be applied at working conditions: evaporator leaving water temperature 7 C Table 6 - Correction factors for water and glycol mixture Ethylene Glycol Ethylene Glycol (%) Cooling Capacity Compressor Power Input Flow Rate (Δt) Evaporator Pressure Drop 10% 20% 30% 40% 50% Propylene Glycol Cooling Capacity Compressor Power Input Flow Rate (Δt) Evaporator Pressure Drop How to use the Correction factors proposed in the previous tables A) Mixture Water and Glycol Evaporator leaving water temperature > 4 C - depending from the type and percentage (%) of glycol filled in the circuit (see table 4.2 and 6) - multiply the Cooling Capacity, the Compressor Power Input by the Correction factor of Table 6 - starting from this new value of Cooling Capacity, calculate the Flow Rate (l/s) and the Evaporatore Pressure Drop (kpa) - now multiply the new Flow Rate and the new Evaporator Pressure Drop by the Correction Factors of Table 6 Example Unit Size: EWWD120J-SS Mixture: Water Working condition: ELWT 12/7 C CLWT 30/35 C - Cooling capacity: 121 kw - Power input: 27.3 kw - Flow rate (Δt 5 C): Evaporator pressure drop: 15kPa Mixture: Water + Ethylene Glycol 30% (for a winter air temperature up to -15 C) Working condition: ELWT 12/7 C CLWT 30/35 C - Cooling capacity: 121 x = 118 kw - Power input: 27.3 x = 26.9 kw - Flow rate (Δt 5 C): 5.64 (referred to 118 kw) x = 6.06 l/s - Evaporator pressure drop: 16 (referred to 6.06 l/s) x = 19kPa page 18/36

19 B) Mixture Water and Glycol Evaporator leaving water temperature < 4 C - depending from the type and percentage (%) of glycol filled in the circuit (see table 4.1 and 4.2 and table 6) - depending from the evaporator leaving water temperature (see table 5) - multiply the Cooling Capacity, the Compressor Power Input by the Correction factor of Table 5 and Table 6 - starting from this new value of Cooling Capacity, calculate the Flow Rate (l/s) and the Evaporatore Pressure Drop (kpa) - now multiply the new Flow Rate and the new Evaporator Pressure Drop by the Correction Factors of Table 6 Example Unit Size: EWWD120J-SS Mixture: Water Working condition: ELWT 12/7 C CLWT 30/35 C - Cooling capacity: 121 kw - Power input: 27.3 kw - Flow rate (Δt 5 C): Evaporator pressure drop: 15kPa Mixture: Water + Glycol 30% (for a low evaporator leaving temperature of 0/-5 C) Working condition: ELWT 0/-5 C CLWT 30/35 C - Cooling capacity: 121 x x = 75.4 kw - Power input: 27.3 x x = 23.7 kw - Flow rate (Δt 5 C): 3.60 l/s (referred to 75.4 kw) x = 3.87 l/s - Evaporator pressure drop: 7 kpa (referred to 3.87 l/s) x = 9 kpa page 19/36

20 Water charge, flow and quality Cooling Water Heated water (2) Cooled Water Circulating System Once Flow Low temperature High temperature Items (1) (5) Tendency if out of criteria Circulating water Supply water (4) Flowing water Circulating water Supply water (4) Circulating water Supply water (4) Circulating water Supply water (4) [Below 20 C] [20 C ~ 60 C] [60 C ~ 80 C] ph at 25 C 6.5 ~ ~ ~ ~ ~ ~ ~ ~ 8.0 Corrosion + Scale Electrical conductivity [ms/m] at 25 C Below 80 Below 30 Below 40 Below 80 Below 80 Below 30 Below 30 Below 30 Below 30 Corrosion + Scale (µs/cm) at 25 C (Below 800) (Below 300) (Below 400) (Below 800) (Below 800) (Below 300) (Below 300) (Below 300) (Below 300) Corrosion + Scale Chloride ion [mgcl 2- /l] Below 200 Below 50 Below 50 Below 200 Below 50 Below 50 Below 50 Below 30 Below 30 Corrosion Sulfate ion [mgso 2-4/l] Below 200 Below 50 Below 50 Below 200 Below 50 Below 50 Below 50 Below 30 Below 30 Corrosion M-alkalinity (ph4.8) [mgcaco 3/l] Below 100 Below 50 Below 50 Below 100 Below 50 Below 50 Below 50 Below 50 Below 50 Scale Total hardness [mgcaco 3/l] Below 200 Below 70 Below 70 Below 200 Below 70 Below 70 Below 70 Below 70 Below 70 Scale Calcium harness [mgcaco 3 /l] Below 150 Below 50 Below 50 Below 50 Below 50 Below 50 Below 50 Below 50 Below 50 Scale Silca ion [mgsio 2/l] Below 50 Below 30 Below 30 Below 30 Below 30 Below 30 Below 30 Below 30 Below 30 Scale Oxygen (mg O2 /l) Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Corrosion Particole size (mm) Below 0.5 Below 0.5 Below 0.5 Below 0.5 Below 0.6 Below 0.5 Below 0.6 Below 0.5 Below 0.6 Erosion Total dissolved solids (mg / l) Below 1000 Below 1000 Below 1000 Below 1000 Below 1001 Below 1000 Below 1001 Below 1000 Below 1001 Erosion Ethykene, Propylene Glycol (weight conc.) Below 60% Below 60% Below 60% Below 60% Below 60% Below 60% Below 60% Below 60% -- Nitrate ion (mg NO3- /l) Below 100 Below 100 Below 100 Below 100 Below 101 Below 100 Below 101 Below 100 Below 101 Corrosion TOC Total organic carbon (mg /l) Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Scale Iron [mgfe/l] Below 1.0 Below 0.3 Below 1.0 Below 1.0 Below 0.3 Below 1.0 Below 0.3 Below 1.0 Below 0.3 Corrosion + Scale Copper [mgcu/l] Below 0.3 Below 0.1 Below 1.0 Below 1.0 Below 1.0 Below 1.0 Below 0.1 Below 1.0 Below 0.1 Corrosion Sulfite ion [mgs 2- /l] Not detectable Not detectable Not detectable Not detectable Not detectable Not detectable Not detectable Not detectable Not detectable Corrosion Ammonium ion [mgnh + 4/l] Below 1.0 Below 0.1 Below 1.0 Below 1.0 Below 0.1 Below 0.3 Below 0.1 Below 0.1 Below 0.1 Corrosion Remaining chloride [mgcl/l] Below 0.3 Below 0.3 Below 0.3 Below 0.3 Below 0.3 Below 0.25 Below 0.3 Below 0.1 Below 0.3 Corrosion Free carbide [mgco 2 /l] Below 4.0 Below 4.0 Below 4.0 Below 4.0 Below 4.0 Below 0.4 Below 4.0 Below 0.4 Below 4.0 Corrosion Stability index 6.0 ~ 7.0 Corrosion + Scale Items to be referred to: Items to be controlled: 1 Names, definitions and units are according to JIS K Units and figures between brackets are old units published as reference only. 2 In case of using heated water (more than 40 C), corrosion is generally noticeable. Especially when the iron materials is in direct contact with water without any protection shields, it is desireable to give the valid measure for corrosion. E.g. chemical measure 3 In the cooling water using hermetic cooling tower, close circuit water is according to heated water standard, and scattered water is according to cooling water standard. 4 Supply water is considered drink water, industrial water and ground water except for genuine water, neutral water and soft water. 5 The above mentioned items are representable items in corrosion and scale cases. 6 The limits above have to be considered as a general prescription and con not totally assure the absence of corrosion and erosion. Some particular combinations of elements or the presence of components not listed in the table or factors not considered may trigger corrosion phenomena. page 20/36

21 Water content in cooling circuits The cooled water distribution circuits should have minimum water content to avoid excessive compressors start and stop. In fact, each time the compressor starts up, an excessive quantity of oil goes from the compressor sump and simultaneously there is a rise in the temperature of the compressor motor s stator due to the inrush current during the start-up. To prevent damage to the compressors, it has been envisaged the application of a device to limit frequent stops and restarts. During the span of one hour there will be no more than 6 starts of the compressor. The plant side should therefore ensure that the overall water content allows a more constant functioning of the unit and consequently greater environmental comfort. The minimum water content per unit should be calculated using this simplified formula: For 1 compressor unit M (liters) = ( 0.94 x ΔT( C) ) x P(kW) For 2 compressors unit M (liters) = ( x ΔT( C) ) x P(kW) where: M minimum water content per unit expressed in litres P Cooling Capacity of the unit expressed in kw ΔT evaporator entering / leaving water temperature difference expressed in C This formula is valid for: - standard microprocessor parameters For more accurate determination of quantity of water, it is advisable to contact the designer of the plant. page 21/36

22 Standard ratings EWWD120~250J-SS ELWT ( C) 15 Entering Condenser Water Temperature ( C) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Notes: Cc (cooling capacity) - Pi (unit power input) - ELWT (Evaporator leaving water temperature - Δt 5 C) - Condenser Water temperature Δt 5 C Data refers to 0,0176 m 2 C/kW evaporator fouling factor Data refers to 0,0440 m 2 C/kW condenser fouling factor page 22/36

23 Entering Condenser Water Temperature ( C) ELWT ( C) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Notes: Cc (cooling capacity) - Pi (unit power input) - ELWT (Evaporator leaving water temperature - Δt 5 C) - Condenser Water temperature Δt 5 C Data refers to 0,0176 m 2 C/kW evaporator fouling factor Data refers to 0,0440 m 2 C/kW condenser fouling factor page 23/36

24 EWWD280~400J-SS Entering Condenser Water Temperature ( C) ELWT ( C) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Notes: Cc (cooling capacity) - Pi (unit power input) - ELWT (Evaporator leaving water temperature - Δt 5 C) - Condenser Water temperature Δt 5 C Data refers to 0,0176 m 2 C/kW evaporator fouling factor Data refers to 0,0440 m 2 C/kW condenser fouling factor page 24/36

25 Entering Condenser Water Temperature ( C) ELWT ( C) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Notes: Cc (cooling capacity) - Pi (unit power input) - ELWT (Evaporator leaving water temperature - Δt 5 C) - Condenser Water temperature Δt 5 C Data refers to 0,0176 m 2 C/kW evaporator fouling factor Data refers to 0,0440 m 2 C/kW condenser fouling factor page 25/36

26 EWWD450~560J-SS Entering Condenser Water Temperature ( C) ELWT ( C) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Notes: Cc (cooling capacity) - Pi (unit power input) - ELWT (Evaporator leaving water temperature - Δt 5 C) - Condenser Water temperature Δt 5 C Data refers to 0,0176 m 2 C/kW evaporator fouling factor Data refers to 0,0440 m 2 C/kW condenser fouling factor page 26/36

27 Entering Condenser Water Temperature ( C) ELWT ( C) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Cc (kw) Pi (kw) Hc (kw) Notes: Cc (cooling capacity) - Pi (unit power input) - ELWT (Evaporator leaving water temperature - Δt 5 C) - Condenser Water temperature Δt 5 C Data refers to 0,0176 m 2 C/kW evaporator fouling factor Data refers to 0,0440 m 2 C/kW condenser fouling factor page 27/36

28 Evaporator and condenser pressure drops EWWD~J-SS Cooling Capacity (kw) Water Flow (l/s) - Evaporator Evaporator Pressure Drops (kpa) Water Flow (l/s) - Condenser Condenser Pressure Drops (kpa) Water flow and pressure drop referred to nominal condition: evaporator water in/out: 12/7 C condenser water in/out: 30/35 C Cooling Capacity (kw) Water Flow (l/s) - Evaporator Evaporator Pressure Drops (kpa) Water Flow (l/s) - Condenser Condenser Pressure Drops (kpa) Water flow and pressure drop referred to nominal condition: evaporator water in/out: 12/7 C condenser water in/out: 30/35 C Evaporator and condenser pressure drops To determinate the evaporator or condenser pressure drop for different versions or at different working condition, please refer to the following formula: PD 2 (kpa) = PD 1 (kpa) x where: Q 2 (l/s) Q 1 (l/s) 1.8 PD 2 PD 1 Q 2 Q 1 Pressure drop to be determinated (kpa) Pressure drop at nominal condition (kpa) water flow at new working condition (l/s) water flow at nominal condition (l/s) How to use the formula: Example (evaporator) The unit EWWD280J-SS has been selected for working at the following conditions: - evaporator water in/out: 11/6 C - condenser water in/out: 30/35 C The cooling capacity at these working conditions is: 277 kw The evaporator water flow at these working conditions is: l/s The unit EWWD280J-SS at nominal working conditions has the following data: - evaporator water in/out: 12/7 C - condenser water in/out: 30/35 C The cooling capacity at these working conditions is: 285 kw The evaporator water flow at these working conditions is: l/s The evaporator pressure drop at these working conditions is: 33 kpa The evaporator pressure drop at the selected working condition will be: PD 2 (kpa) = 33 (kpa) x 13,23 (l/s) (l/s) 1.8 PD 2 (kpa) = 31 (kpa) NOTE If the calculated evaporator water pressure drop is below 10 kpa or above 100 kpa please contact the factory for dedicated evaporator. page 28/36

29 Dimensions EWWD~J-SS / 1 circuit Models Dimensions (mm) EWWD~J -SS A B C D E F G H LEGEND 1. Compressor 2. Evaporator 3. Condenser 4. Electrical panel 5. Evaporator water inlet 6. Evaporator water outlet 7. Condenser water inlet connection 8. Condenser water outlet connection 9. Power connections slot page 29/36

30 EWWD~J-SS / 2 circuits Note. Dimension refers to 2 circuit units (size from ). LEGEND 1. Compressor 2. Evaporator 3. Condenser 4. Electrical panel 5. Evaporator water inlet 6. Evaporator water outlet 7. Condenser water inlet connection 8. Condenser water outlet connection 9. Power connections slot page 30/36

31 Installation notes Warning Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and regulations, and who are experienced with this type of equipment. Must be avoided the unit installation in places that could be considered dangerous for all the maintenance operations. Warning Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and regulations, and who are experienced with this type of equipment. Must be avoided the unit installation in places that could be considered dangerous for all the maintenance operations. Handling The chiller is mounted on heavy wooden skids to protect the unit from accidental damage and to permit easy handling and moving. It is recommended that all moving and handling be performed with the skids under the unit when possible and that the skids not be removed until the unit is in the final location. If the unit must be hoisted, it is necessary to lift the unit by attaching cables or chains at the lifting holes in the evaporator tube sheets. Spreader bars must be used to protect the control cabinet and the other areas of the chiller. Location A leveled and sufficiently strong floor is required. If necessary, additional structural members should be provided to transfer the weight of the unit to the nearest beams. Rubber-in-shear isolators can be furnished and field placed under each corner of the package. A rubber anti skid pad should be used under isolators if hold-down bolts are not used. Vibration isolator in all water piping connected to the chiller is recommended to avoid straining the piping and transmitting vibration and noise. Minimum space requirements Every side of the machine must be accessible for all post-installation maintenance activities. The minimum space required is shown on the following drawing: Top view Side view Minimum clearance requirements for machine maintenance page 31/36

32 Technical specification for water cooled screw chillers General The water cooled screw chiller will be designed and manufactured in accordance with following European directives: Construction of pressure vessel Machinery Directive Low Voltage Electromagnetic Compatibility 97/23/EC (PED) 2006/42/EC 2006/95/EC 2004/108/EC Electrical & Safety codes EN / EN Manufacturing Quality Stds UNI EN ISO 9001:2004 The unit will be tested at full load in the factory at the nominal working conditions and water temperatures. Before shipment a full test will be held to avoid any losses. Chiller will be delivered to the job site completely assembled and charged with right refrigerant and oil quantity. Comply with the manufacturer instructions for rigging and handling equipment. The unit will be able to start up and operate as standard at full load and condenser entering fluid temperature from. C to. C with an evaporator leaving fluid temperature between. C and C All units published performances have to be certified by Eurovent. Refrigerant Only HFC 134a will be accepted. Performance Number of water cooled screw chiller:... Cooling capacity for single water cooled screw chiller:... kw Power input for single water cooled screw chiller in cooling mode:... kw Plate to plate evaporator entering water temperature in cooling mode:... C Plate to plate evaporator leaving water temperature in cooling mode:... C Plate to plate evaporator water flow:... l/s Shell & tube condenser entering water temperature in cooling mode:... C Shell & tube condenser leaving water temperature in cooling mode:... C Shell & tube condenser water flow:... l/s The unit should work with electricity in range 400V ±10%, 3ph, 50Hz without neutral and shall only have one power connection point. Unit description Chiller shall include as standard: 1 or 2 independent refrigerant circuits, semi-hermetic rotary single screw compressors, electronic expansion device (EEXV), direct expansion plate to plate evaporator and shell & tube condenser, R134a refrigerant, lubrication system, motor starting components, control system and all components necessary for safe and stable unit operation. Chiller will be factory assembled on a robust base-frame made of zinc coated steel, protected by an epoxy paint. Noise level and vibration Sound pressure level at 1 meter distance in free field, semispheric conditions, shall not exceed db(a). The sound pressure levels must be rated in accordance to ISO Other types of rating unacceptable. Vibration level should not exceed 2 mm/s. Dimension Unit dimensions shall not exceed following indications: unit length... mm, unit width... mm, unit height... mm. page 32/36

33 Chiller components Compressors Semi-hermetic, single-screw type with one main helical rotor meshing with gaterotor. The gaterotor will be constructed of a carbon impregnated engineered composite material. The gaterotor supports will be constructed of cast iron. The oil injection shall be used in order to get high EER (Energy Efficiency Ratio) also at high condensing pressure and low sound pressure levels in each load condition. Refrigerant system differential pressure shall provide oil flow throught service replaceble, 0.5 micron, full flow, cartridge type oil filter internal to compressor. Refrigerant system differential pressure shall provide oil injection on all moving compressor parts to correctly lubricate them. Electrical oil pump lubricating system is not acceptable. The compressor s oil cooling must be realized, when necessary, by refrigerant liquid injection. External dedicated heat exchanger and additional piping to carry the oil from the compressor to heat exchanger and viceversa will be not accepted. The compressor shall be provided with an external, high efficiency, cyclonic type oil separator and with built-in oil filter, cartridge type. The compressor shall be direct electrical driven, without gear transmission between the screw and the electrical motor. Shall be present two thermal protection realized by a thermistor for high temperature protection: one temperature sensor to protect electrical motor and another sensor to protect unit and lubricating oil from high discharge gas temperature. The compressor shall be equipped with an electric oil-crankcase heater. Compressor shall be fully field serviceable. Compressor that must be removed and returned to the factory for service shall be unacceptable. Cooling capacity control system Each unit will have a microprocessor for the control of compressor slide valve s position and the instantaneous RPM value of the motor. The unit capacity control shall be infinitely modulating, from 100% down to 25% for each circuit (from 100% down to 12,5% of full load for unit with 2 compressors). The chiller shall be capable of stable operation to a minimum of 12,5% of full load without hot gas bypass. Step unloading unacceptable because of evaporator leaving water temperature fluctuation and low unit efficiency at partial load. The system shall stage the unit based on the leaving evaporator water temperature that shall be controlled by a PID (Proportional Integral Derivative) loop. Unit control logic shall to manage frequency level of the compressor electric motor to exactly match plant load request in order to keep constant the set point for delivered chilled water temperature. In this operating condition unit control logic shall modulate electrical frequency level in a range lower and upper the nominal electrical network value fixed at 50 Hz. The microprocessor unit control shall detect conditions that approach protective limits and take self-corrective action prior to an alarm occurring. The system shall automatically reduce chiller capacity when any of the following parameters are outside their normal operating range: o High condenser pressure o Low evaporation refrigerant temperature o High compressor motor amps Evaporator The units shall be equipped with a Direct Expansion plate to plate evaporator with copper tubes rolled into steel tubesheets. The external shell shall be linked with an electrical heater to prevent freezing down to -28 C ambient temperature, controlled by a thermostat and shall be insulated with flexible, closed cell polyurethane insulation material (10 mm thick). The evaporator will have 1 circuit. The water connections shall be threaded type connections as standard to ensure quick mechanical disconnection between the unit and the hydronic network. Evaporator is manufactured in accordance to PED approval. page 33/36

34 Condensers Condensers will be shell and cleanable, through-tube type. The unit will have one condenser per circuit. Each condenser shall have a carbon steel and seamless, integrally finned high efficiency copper tubes, roll expanded into heavy carbon steel tube sheets. Water heads shall be removable and include vent and drain plugs. Condensers will come complete with liquid shut-off valve, spring loaded relief valve. Refrigerant circuit Each circuit shall include as standard: electronic expansion device piloted by unit s microprocessor control, compressor discharge shut-off valve, suction line shut-off valve, replaceable core filter-drier, sight glass with moisture indicator and insulated suction line. Control panel Field power connection, control interlock terminals, and unit control system should be centrally located in an electric panel (IP 54). Power and starting controls should be separate from safety and operating controls in different compartments of the same panel. Starting shall be Wye-Delta type as standard. Operating and safety controls should include energy saving control; emergency stop switch; overload protection for compressor motor; high and low pressure cut-out switch (for each refrigerant circuit); anti-freeze thermostat; cut-out switch for each compressor. All of the information regarding the unit will be reported on a display and with the internal built-in calendar and clock that will switch the unit ON/OFF during day time all year long. The following features and functions shall be included: - resetting chilled water temperature by controlling the return water temperature or by a remote 4-20 ma DC signal or by controlling the external ambient temperature; - soft load function to prevent the system from operating at full load during the chilled fluid pulldown period; - password protection of critical parameters of control; - start-to-start and stop-to-star timers to provide minimum compressor off-time with maximum motor protection; - communication capability with a PC or remote monitoring; - discharge pressure control through intelligent cycling of condenser fans; - lead-lag selection by manual or automatically by circuit run hours; - double set point for brine unit version; - scheduling via internal time clock to allow programming of a yearly start-stop schedule accommodating weekends and holidays. Optional High Level Communications Interface The controller as a minimum shall be capable of providing the data shown in the above list, using the following options: - RS485 Serial card - RS232 Serial card - LonWorks interface to FTT10A Transceiver. - Bacnet Compatible - Use of Compass Points (manufactured by North Communications) to allow communications with such as Honeywell, Satchwell, Johnson Controls, Trend etc. page 34/36

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